In Diamond/Pearl, the rival's final team ended up being more powerful than Red in GSC. In HGSS, they bumped Red up, to once again being the strongest NPC to face against. I would have been upset if they didn't let Red reclaim this placing.

In a game which allows you to grind up to lv100, I wish there were more opponents to challenge at levels that isn't just "press A, press A, press A", i.e. grinding.

EDIT: Also, no credits appear after beating Red. Really, the entire Kanto thing is just a sidequest, not required. It makes the path to lv100 more enjoyable than just beating the Elite 4 a thousand times. My team was around lv80 when I beat him, so this just gave me a milestone before hitting lv100.